<div class="user-field-mobile-value" id="user-field-mobile-value">
  <input type="text" name="mobile_text" id="mobile_text" value="<%=params[:mobile]-%>">
</div>

<div class="change-user-field">
<%= link_to_remote "Update" ,:url => {:controller=>"post",:action => "update_mobile",:id => params[:id]} ,:with => "'mobile_text=' + $('mobile_text').value", :update => "user-field-mobile" -%>
</div>

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